Problems with CF card

I am getting my butt kicked by this cf card. It is a 4GB Sandisk Ultra, brand new. I put it in my reader and it shows up as a drive. I follow the directions for physdiskwrite and nothing is happening. Physdiskwrite does not even show the disk being there, it shows my hard drive and thats it. I am running Windows 7 Ultimate. Any ideas would be helpful, and thanks.

Thanks, but I had been. Come to find out it was two bad card readers, and one was brand new. One of my guys took it home and plugged it into his card reader and it worked fine. Such is life. Thanks again for the tip.